Internal combustion engine



INTERNAL COMBUSTION ENGINE lFiled oct. 1s, 195o 2 sheets-sheet 1vAsis/Au: d Asse/m #A5, u A

De :.l15,- 1936.. D. J. 'DESCHAMPS INTERNAL COMBUSTIN ENGINE Filed OGL.13, 1930 2 ,Sheets-Sheet 2 Pmwm A, A

Patented Dec. 15,v 1-936 o UNITED STATES PATENT OFFICE INTERNAL COMBUSTION ENGINE Desire J, Deschamps, st. Louis, Mo., assigner of one-halfto P. De C. Ball, St. Louis, Mo.

Application October 13, 1930, Serial No. 488,222

3 Claims. (Cl. 123-4-59) This invention relates generally to two strokeof an internal combustion engine constructed internal combustion enginesof the compression in accordance with this invention; ignition typegenerally known as Diesel engines Figure 2 is a sectional view, takenalong the and more particularly to such engines which line 2 2 of Figurel;

are adapted to operate at high speeds suitable Figure 3 is a view inside elevation showing 5 for use in automobiles and aircraft.particularly the manner of driving the sleeve Heretofore internalcombustion engines of this valves f of this invention; type have beensuccessfully operated at com- Figure 4 is a perspective view of a valveele- Daratively' low speeds for industrial purposes, ment employed inaccordance with this invenbut such engines have not been capable ofopertion;

ation Vat the high speeds .required for engines Figure 5 isa detail viewin lend elevation of in aircraft and automobiles'. 'Ihe most imporanelement for connecting the valve sleeve with tant limiting featureswhich prevent the use of its drive shaft; and

such engines as haveheretofore been known, for Figure 6 is a detail viewin side elevation of automotive purposes, are the fuel injection systheconnecting element showmin Figure A5.. 15 tem and the distributionmechanism. In a two In accordance with this invention, a two- Strokecycle engine, power output and the` spestroke internal combustion engineof the comcic fuel consumption are principally dependpression ignitiontypethat is an engine in ent upon the eicacy of scavenging of thecylinwhich ignition takes place by the injection of ders. The scavengingmust be accomplished in a quantity of fuel into a chamber inf'which a arelatively short time, during the short part denite volume of air hasbeen highly com- Of the stroke 'of the piston that the exhaust pressedso that 'the temperature is suflicient to ports remain open, and thiscannot be thorignite the fuel-is provided with a rotary sleeve oughlyaccomplished by the methods hereto valve operating in a solid housingand at a speed fore employed in slow and medium speed enless than thespeed o'f the crank shaft of the gines. 'Ihe prior distributionmechanisms and engine and preferably at a speed equal to onescavengingsystemshave not provided a sumhalf of the crank shaft speed. If operatedat cient section for the passage of the exhaust half of the crank shaftspeed, the valve is progases and the admission of the scavenging air,vided with diametrically opposite ports, which furthermore, the relativelocation of the inlet open upon each receding stroke ofthe piston andoutlet ports have caused the scavenging air to admit to the cylinder aquantity of slightly to mix to some extent with the exhaust gases,compressed air for removing the fumes` from and, consequently, on thenext succeeding cycle the cylinder and which operation is known as thecylinder is partly lled with burned gases, scavenging. As is customaryin usual practice, so that efcient operation and complete com-v the onepiece. valve housing and the rotary 35 bustion are impossible. sleevevalve extend along over the head of the Thelobject of this invention is,as generally several cylinders of the engine, which necessistated,"t'oprovide p, two-stroke internal combus.. tates'the use of a. verylong-valve in case of a tion engine `of the compression ignition type.multi-CylindeT-m'lne engineln addmon t0 40 which is capable ofOpel-ation at high Speeds the inherent diiiiculty of accuratelymachining 40 Another object of this invention is to pro such a longsleeve, experience has shown that vide a rotary sleeve valve mechanismfor a two'- in such a' long Valve housing and valve. shgho ystrokeinternal combustion engine which shall distortions are caused by theuneven dostribu' be operated at a speed less than the crankshaft tion ofthe heat to egect .noven expanslon and speed of the enginecontraction.'lhese distortions may be of such A more specific object of thisinvention is to extent as to Shghtly bend the valve or the nous' ing andcause the valve@ to freeze in its housing provide a valve mechanismwhich shall have a minim n ber of moving parts. by undue increase oflocal pressure between the f; valve and its housing. other obleots ofons loventlon Wm become The sleeve valve arrangement which is'con- 50apparoot to thoso sklued m' the art when 12h@ templated by thisinvention involves a plurality following description isread 1nconnection with of sleeve sections having a, uniform rotarymovethe,accompainymg dramgs m Whlchment in a. solid housing, which acts asabear- Flgure, 1 1S. a view m side elevation, shown ing for the same.The sleevesections are driven partly in sectlon to reveal the operatmgparts by a single slightlynexible drive shaft coaxial 55 therewith,through couplings centered in the bore of the valve elements and somounted as to eliminate the possibility of so-called freezing betweenthe valve elements and the housing within which they rotate. It will beapparent that by the division of the sleeve valve into a plurality ofsections, relative movement between the sections is possible, so that nobinding occurs incident to uneven expansion and contraction of thehousing. As hereinbefore stated the cylindrical valve sleeves rotate ina solid housing. By the term solid housing it will be understood thatthe housing .includes an integral cylindrical bore and that no specialmechanical devices are used to control the running clearance between thevalve and the housing at the various operating temperatures of theengine. The necessity for such mechanical devices is eliminated by thisinvention wherein use is made of especially selected metals for theconstruction of the rotary sleeve valve and its housing.

Referring now to the drawings, an internal combustion engine ofthecompression ignition type is shown in inverted position, in whichposition it is preferably operated in aircraft.

The engine of this invention comprises a block i having a plurality ofcylinders `I, I D, etc., and

Within each cylinder is slidably mounted a piston 2 in a manner Wellknown in the art. As hereinbefore stated, the cylinders are in alignedrelation within a cylinder block 3 so that the pistons 2 in eachcylinder may transmit a power stroke to a common crank shaft. A head 4is provided for closing the end of the cylinders I, I0, etc., and isformed of a single casting extending across the entire block 3. WithinAthe head 4, an integral cylindrical bore 5, extending longitudinallythereof, is formed so that the solid housing, hereinbefore mentioned,remains. The cylindrical housing 5 communicates with each of thecylinders I, I0, etc., through ports 6, 50, etc., which extend throughthe wall of the head 4 so as to provide a passage between the sleeve andthe cylinder. The head 4 and the block 3 are each provided with jacketshaving spaces `I for the circulation of the cooling medium.

Aslightly flexible shaft 81 is disposed coaxially IWithin the bore 5 andis supported by a suitable bearing cap 9. It will be observed that thebearing cap 9 forms a closure for one end' of the valve housing 5. Abevel gear I I is secured to the shaft 8 at the end thereof outside thecap 9. A bevel' gear I2 is mounted upon the end of a shaft I3 forcooperation with the bevel gear A II to drive the shaft 8 by power fromthe crank shaft of the engine, which may be delivered to the shaft I3through any suitablel power-transmitting mechanism. It may be herepointed out that the power-transmittingV mechanism employed with theembodiment illustrated in the drawings is such that the shaft 8 rotatesat a speed equal to one-half of the speed ofthe crank shaft of theengine. Y

Within the cylindrical housing 5, a plurality of.valve elements I4,,I5,v I6, are disposed each of which is adapted to serve a pair ofadjacent cylinders, such as I and I0. For the purpose of illustration,these valve .elements are provided three in number, since`- the engineillustrated is of the six cylinder type. Each of the valve elements I4,I5, and I6, is mounted for a close running t within the cylindricalhousing 5, so that rotation of the element within the housing ispossible. As is clearly illustrated in Figures 1 and 4, the valveelement I4 is provided with a pair of diametrically opposite openingsI'I and I8 through the wall thereof, which are disposed directly abovethe port 6 through the wall of thev cylinder head 4, and it will beclearly apparent that upon rotation of the valve element I4, theopenings I1 and I8 will alternately come into such a position vthat apassage is opened between the inside of the valve element I4 and the.cylinder I. Since the valve element I4 serves two cylinders of theengine, another pair of diametrically opposite openings such as I9 isprovided directly above the adjacent cylinder I0, which upon rotation ofthe element I4 will become disposed opposite the port 60 of the cylinderI Il to open a passage thereto at the proper time during the operatingcycle of the cylinder III.

Referring now particularly to Figure 4, it will be seen that thevalveelement I4 is provided about its circumference with a plurality ofcircumferentially extending grooves 20, 2| and 22, located symmetricallyon each side of the ports I1, I8 and I9. It will'be noted that thegrooves 2D are provided with angular extensions, such as 23, extendingfrom the groove toward the openings of the valve. The orientation ofthese angular extensions 23 is such that they operate to dispellubricant by its inertia upon.the rotation of the valve element 4I4,.tothereby form and maintain a lm of lubricant between the bore of thecylindrical housing 5.

In the wall of the valve housing 5 aredrllled a plurality of smallcalibrated holes which are in communication with a suitable oil line(not shown) extending along the outer wall of the valve housing 5, thisoil line may be connected with the main lubricating system of theengine. One such calibrated hole is disposed directly over each groove20, so that lubricant is fed to the sleeve'element I4 at the pointsindicated by arrows in Figure 4, filling the grooves 20 from which it isdispelled over the entire surface of the .valve element I4. The othercircumferential grooves 2I and 22 act as small oil reservoirs andhydraulic rings which coact with the lubrieating oil lm to assure thesealing of the cylindrical valve element in its housing 5, so as toprevent the escape of gases to adjacent cylinders through the clearancebetween the walls of the housing 5 and the valve element I4 such as, forinstance, between the ports 6 and 60. The

disposition of these grooves is, of course, similar 'circular grooves22. 'It will be noticed also that no longitudinal grooves 24 areprovided on the portion of surface of the valve element I4, which coversthe intake port 6 during the phase of the cycle when the pressure in thecombustion chamber of the cylinder is at its maximum value, that f iswhen the piston 2 is at its top dead centerl position at whichtimecombustion of the injected fuel begins.

"amico .these coupling members 2l and 28 are keyed .to

the drive shaft 8 fr rotation therewith. The coupling 21 drives both thevalve elements Il and I5, whileV the coupling 28 drives only the lastvalve element I5. Any. number of valves may, of course, be driven bysuch connections. Where there is an even number of valves acoupling suchas 21 may be arranged to drive each pair. Where there is an odd numberof valves, the odd one may be driven by a coupling'such as 28. Aspreviously stated, the shaft 8 is sup-f ported near one end thereof inthe bearing 8, so that the elasticity of the metal permits. limitedflexing of the lextended portion within thehousing 5. The shaft 8 iscentered in the valve elements -by the coupling members 21 and 28, whichare provided with-extensions 28, engage with a sliding t within the boreof the'valve element and cooperate with the tongue 28 to center thecoupling in .the valve element.

The valve elements being thus lnslidable engagement with the couplings21 and 28, a limited axial movement of the" valve elements -relative tothe shaft 8 is possible when the opposedends of adjacent valve elementsdo not abut eachl v8 is of a tubular and somewhat ilexible construction;being substantially free at the end within the housing 5, it permitsslight distortions of the valve housing 5 without aifecting the seatingor freedom of'movement of the valve elements in the housing. In thisway, the operation of the valve elements is not impairedby slightbending of the housing incident to uneven expansion and contraction. Y

Since it is necessary that the valve elements Il, I5, and I8 berotatable within the cylindrical housing 5 and at the same timefitted\therein with sufficient closeness to prevent .the escape of gasesfrom one cylinder through the housing 5 to an adjacent cylinder, andsince both the valve elements and the cylinder head are subject toconsiderable expansion due to the heat of combustion within the engine;it is necessary that provision be made to maintain an even clearancebetween the valve element and the housing 5.

Furthermore, since it is customary in engines of this type to water coolcylinder heads, the wall of the housing 5 will be constantly cooled bythe circulation of lwater thereabout, and in this way Ithe expansion ofthe valve elements will be greater than the expansionof the sleeve 5which surrounds them. Although the valveelementsdissipate some heatwhich they receive from the hot gases in the cylinder to the air whichcirculates through the valve elements and by contact with the cooledwalls of the valve housing, it is apparent that less heat will bedissipated by I the `valve elements than is dissipatedby the housing 5to the cooling water and, accordingly greater expansion' will occur inthe .valve elementsthan occurs in the housing 5.` In order to maintainthe desirable clearance between the valve elements and the sleeve 5under all temperature conditions, so that a close ilt will exist betweenthese elementsto prevent the, flow of gases therebetween and to 'permit-rotation ofl the valve elements. it is desirable that the casting whichcomprises the cylinder'head l and the housing 5, be formed of aImaterial having a higher coeillcient of expansion than the valve thanthe surrounding sleeve 5, the valve elements are preferably formed of ametal having a lower coeillcient of expansion than-the housing 5, and

A heat treated hard alloy steel has been found to be well suited forthis purpOSe.. 4Bythus providing a valve element of hard stcel and anouter bearing or housing of a suitable aluminum alloy for snugAengagement therewith, within which the element is rotatable, it will befound ing 5 to causeexpansion thereof;' and although the sleeve 5 is ata lower temperature than the takes place in the sleeve 5 is, due to itshigher coefficient of expansion, substantially equal to the amount ofexpansion which takes place in the valve elements, so that the fitbetween these parts is not changed. Furthermore, the bearing qualitiesof these metals are such as to be extremely desirable for conjoint use.

A plurality ofv exhaust ports 3| areprovided about the wall of thecylinder in such a position that they will be opened by the downwardmovement of the piston 2 when approaching the end of its travel; and itwill be understood that the 'powertransmitting mechanism between'thecrank shaftl of the engine and the shaft 8 is such'that one of theopenings I1 or I8 in the valve sleeve I4 comes into engagement with theport 6 shortly after the time when the exhaust ports are opened by themovement of the piston 2.

In the operation of an internal combustion engin'e provided with a valveof this-sort, a supply of slightly compressed air is Aadmitted to anelbow at one end of the housing 5 and deliveredwithin the valve elementI6. It will thus be seen that the valve elements I4, I5 and I6 act as aconduit for conducting slightly compressed air to the various cylindersupon the opening of the inlet ports 6 thereof. It will be recalled thatin the embodimentillustrated, the valve elements I4, I5, and I8 arerotated by the drive shaft 8 ata speed `equal to half. the speed ofrotation of the crank shaft of the engine, and' it is thus ap-v parentthat each time the piston 2 of the cylinder approaches the positionindicated in Figure 1,

one ofthe openings Il or I8 will come adjacent rthe inlet port. 5topermit an inrush of scavenging air from the valve element I 4 toblowthe exhaust gases to the exhaust ports 3| and illl the cylinder Iwitli clean air.y

valve element I4, the amount of expansion which The air inlet portiopens a certain. time after I the exhaust ports 3| are opened by thedownward movement ofthe piston, Fby this fact the exhaust period becomesthus divided in two distinct periods. The first period, which can belcalled the exhaust period at highvpressure, ex-

tends from the moment the exhaust ports 3| are opened until vthe airinlet port 6 is opened. During that period the greater part of theburned* gases Aeseapetlirough the exhaust ports; being I forced out bythe high pressure still remaining in the cylinder after the combustionof the fuel.

'I'he second period, which is much'longer than 75 to permit the inrushof the slightly compressed scavenging air; this scavenging air travelstoward the exhaust ports 3l, forcing the remainder Y of the burned gasesout of the cylinder.

When the piston 2 nears its top dead `center position-or, in otherwords, when the crankshaft of the engine has rotated through 180degrees, a supply of fuel is injected into the cylinder through one ofthe nozzles 39 in a manner more fully described in my copendingapplication Serial No. 482,956 led September 19, 193i).

Since it is apparent that many modications will present themselves tothose skilled in the art and that many sub-combinations are of utilitywithout reference to other features or sub-combinations, it is to bedistinctly understood that such modifications and sub-combinations as donot depart from the spirit of this invention, although not specicallydescribed herein, are contemplated by and are within the scope of theappended claims. It is to be furthermore understood that the embodimenthere shown and described shall be considered merely illustrative and notin a limiting sense.

Having thus described the invention, what is claimed is:

1. A valve mechanism for a two-stroke inter-` nal combustion engine,comprising, a cylindrical housing having ports communicating with thecylinders of the engine, a plurality of valve elements disposedcoaxially within said housing,

a cantilever shaft supported at one end of said housing forrotating-said elements in unison, and means for centering the free endof said shaft within said housing.

2. A valve mechanism for an internal-combustion engine, comprising acylindrical housing having ports communicating with the cylinders of theengine, -a plurality of successively positioned valve elements disposedcoaxially for independent alinement in said housing and having portscooperating with said rst ports, and a single driving element to whicheach'of said successive Valve elements is individually and looselyconnected so as to permit such independent alinement, said drivingelement being thereby connected to drive all of said valve elementssimultaneously and in xed relation with each other. Y

3. In an internal combustion engine of the characterdescribed having aplurality of longitudinally arranged cylinders, a valve housing having abore extending along the line of cylinders and having portscommunicating with each of the cylinders, and a valve coaxially mountedfor rotation in said. bore, ysaid valve having a circumferentiallycontinuous part snugly tting said bore intermediate said ports, saidhousing being constructed of a metal having a greater coeflicient ofthermal expansion thanvthe metal of which the valve is constructed.

DESIRE J. DESCHAMPS.

